Concrete pavement cutting machine

ABSTRACT

A self-propelled pavement cutting machine comprising a drive truck having a front end having an upright sliding coupling with the rear of a vehicle having an elongated cutter for cutting bumps or grooves, the vehicle having front wheels and rear wheels. When the cutter is active, the vehicle is supported by its two sets of wheels, depth control means being provided for the cutter. The truck has a pump supplying hydraulic fluid to raise and support the rear end of the vehicle with its cutter and rear wheels, the vehicle being supported then by its front wheels. When the vehicle is being pushed by the truck, side sway of the vehicle is prevented as the coupling is arranged on opposite sides of the longitudinal center of the truck and vehicle.

United States Patent 1 3,697, Hatcher et al. [451 Oct. 10, 1972 [s41CONCRETE PAVEMENT CUTTING Primary Exdminer-Emest R. Purser MACHINE [72]Inventors: Cecil W. Hatchet; Gene Warner, both of PO. Box 1263, ElMonte, Calif. 91734 [22] Filed: Feb. 25, 1971 [21] Appl. N0.: 118,909

[52] US. Cl ..299/39, 173/24 [51] Int. Cl ..E0lc 23/09 [58] Field ofSearch 299/39, 41; 173/24 [56] References Cited UNITED STATES PATENTS2,223,213 11/1940 Kersten ..299/39 X 3,407,005 10/ 1968 Simms et a1..,.l73/24 X 3,606,467 9/197'1 Christensen et al....'... ..299/39Attomey-William E. Beatty ABSTRACT A self-propelled pavement cuttingmachine comprising a drive truck having a front end having an uprightsliding coupling with the rear of a vehicle having an elongated cutterfor cutting bumps or grooves, the vehicle having front wheels and rearwheels. When the cutter is active, the vehicle is supported by its twosets of wheels, depth control means being provided for the cutter. Thetruck has a pump supplying hydraulic fluid to raise and support the rearend of the vehicle with its cutter and rear wheels, the vehicle beingsupported then by its front wheels. When the vehicle is being pushed bythe truck, side sway of the vehicle is prevented as the coupling isarranged on opposite sides of the longitudinal center of the truck andvehicle.

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CONCRETE PAVEMENT CUTTING MACHINE CROSS-REFERENCE TO RELATED APPLICATIONV PAVEMENT CUTTING MACHINE, Ser. No. 119,476, filed Mar. 1, l97l, byCecil W. I-Iatcher et al.

BACKGROUND OF THE INVENTION 1. Field of the Invention This inventionrelates to concrete pavement cutting machines and has particularreference to machines having axially spaced, rotatable, abrasive disksengagable with the pavement to remove bumps or the like or to cutanti-skid grooves therein.

2. Description of the Prior Art Concrete cutting machines have beenemployed heretofore, cutting the surfaces of highways, airplane landingstrips, or the like. Certain machines, as disclosed, for example, inU.S. Pat. No. 3,037,755, issued on June 5,-1962, have been developed forremoving bumps or small rises in pavement which might affect the smoothriding of the vehicle. Others, as disclosed in U.S. Pat. No. 3,269,775,issued on Aug. 30, I966, have been developed to cut closely spacedgrooves inthe pavement to reduce skidding tendencies of vehiclestraveling thereon. g

Although such machines have been generally satisfactory, they arerelatively expensive to manufacture and are normally useful only for thespecific purpose for which they were designed. Also, the drive wheels ofsuch machines normally support one end of the framework carrying thecutter. Adjusting means is provided to adjust the height of theframework to regulate the depth of cut. Because of this, the drivewheels must be arranged to run or track in the path cut by the cutter inorder to closely control the depth of cut.

SUMMARY OF THE INVENTION A principal object of the present inventionisto provide a simple and economically manufactured machine for cuttingthe surface of a pavement.

Another object is to provide a machine of the above type which may bequickly and readily adapted to either remove bumps or to cut anti-skidgrooves.

Another object is to provide an adjustable depth-ofcut control meanswhich is independent of the means for raising or lowering the framesupporting the cutter.

A further object is to embody a conventional forklift truck, withcertain modifications, as an operating component of a concrete cuttingmachine.

The present invention, preferably, although not necessarily, embodies aconventional forklift truck in which only one set of coaxial drivewheels are retained to act as the prime mover. The truck carries a mastas sembly along which a carriage is movable. The carriage is attached tothe rear end of a cutter frame, which is supported by vehicle wheels atits front and rear ends for movement over the pavement.

The rotary cutter is supported by the frame; and by raising the carriageunder control of an operator on the truck, the cutter and its rearwheels can be readily raised to a transporting position, the front endof the frame being supported by the front vehicle wheels, so that it maybe driven at high speed from place to place. The carriage may be loweredto a cutting position wherein the frame is supported by the front andrear vehicle wheels. Accurate control of the depth of cut is effected bytransversely spaced arms pivoted on the frame and carrying wheeledsupports engagable with the pavement. Adjustable stopmeans limitspivotal movement of the arms to thus accurately control the depth ofcut.

When a cutter having more widely spaced abrasive disks is employed tocut anti-skid grooves, additional wheeled supports are attached to thepivoted arms and are adjustable to accurately control the depth of cutindependently of the lowered position of the cutter frame. Accordingly,the truck drive wheels may be located inside or outside the path of outwithout affecting the depth of cut.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a side elevational view of amachine embodying a preferred form of the present invention.

FIG. 2 is a transverse sectional view taken along line 2-2 of FIG. 1.

FIG. 3 is a sectional plan view taken substantially along line 3-3 ofFIG. 1.

FIG. 4 is a fragmentary perspective view of one of the cutting depthcontrol arms.

FIG. 5 is a fragmentary sectional side view showing one of the controlarms in depth-limiting position, as used in cutting bumps or smallrises.

FIG. 6 is a view similar to FIG. 1 but showing the machine raised intransporting position.

FIG. 7 is a view similar to FIG. 5 but showing an adjustable auxiliarywheeled support attached to one of the depth control arms, as used incutting anti-skid grooves.

FIG. 8 is a schematic diagram of the hydraulic controls.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to the drawings, themachine comprises, in general, a truck 11 coupled to a cutter vehicle11'. The truck 11 is supported by a single set of coaxial drive wheels,one of which is shown at 12. An upright mast assembly 13 is attached tothe truck frame 14 by brackets 15 and comprises inwardly facingU-channel members 16 and 17, FIG. 3, along which a carriage 18 ismovable. The carriage comprises a vertical plate 20 carrying twovertically spaced rollers 21 and 22 which move along the channel member17, and two similar rollers which move along the channel member 16,upper roller 21' appearing in FIG. 3. The plate 20 is welded orotherwise attached to the rear cross member 23 of a cutter supportingframe 23. When the vehicle 11' is being pushed by truck 11, side sway ofvehicle 11' is prevented as the slide couplings including channelmembers 16 and 17 are laterally spaced apart on opposite sides of thelongitudinal axis of the truck 11 and vehicle 11'.

An engine 24 is carried by the truck 11 and is connected to the drivewheels 12 through a drive train comprising a fluid coupling 24, amulti-speed transmission 25, and a differential 26.

As shown in FIGS. 1 and 6, a hydraulic cylinder 27 is secured at 28 tothe lower end of the mast assembly 13, and its piston rod 27' isconnected at 30 to a bracket fixed to the carriage plate 20, wherebyextension of the piston will raise the rear end of the frame 23 whichtilts about the horizontal axis of the front wheels 38, 40.

The aforementioned truck 11 preferably comprises a conventional forklifttruck from which a second set of wheels and the usual fork attached tothe carriage have been removed. A seat 31 is provided for the operator,and various controls, including a steering wheel 32, are mounted on anupright part of the truck frame within easy reach of the operator.

The frame 23 comprises spaced side frame members 33 and 34, FIG. 3, andintegral cross members 23', 35,

36 and 37. The frame 23 is supported at its forward end by spaced,steerable wheels 38 and 40, which support an axle 41 suitably attachedto the frame 23. A poweroperated steering linkage is provided,comprising cross links 42 and 43 connected between the bearing supportsof the wheels and a crank 44 pivoted at 45 and operable by the piston ofa hydraulic cylinder 46 mounted on the cross member 36.

A rotatable concrete cutter, generally indicated at 47, is provided,comprising a plurality of closely spaced abrasive cutting disks 48secured on a cutter shaft 50 (FIGS. 1, 2 and 3). The latter is rotatablymounted in bearings 51 and 52 suitably secured to pillow blocks 53 and54 integral with the side frame members 34 and 33, respectively.

For the purpose of removing bumps, etc., the disks 48 are preferablyclosely spaced, with the spaces therebetween being on the order of 0.020to 0.025 inches, and are rotated counterclockwise, as viewed in FIG. 1,at a relatively high peripheral speed. For this purpose, an engine 55 ismounted on the forward part of the frame 23 and drives the cutterthrough a drive train including a clutch 56 and a differential unit 57,output shaft 58 of which is journaled in bearings 60 and 61 supported bythe frame 23. Pulleys 62 and 63 are secured to the outer ends of theshaft 58 and drive pulleys 64 and 65 secured to the cutter shaft 50through sets of drive belts 66 and 67, respectively.

The cutter 47 is selectively driven by engaging the clutch 56; and forthis purpose, the clutch is controlled by a hydraulic clutch engagingcylinder 68 under control of the truck operator, as will appear later.

Means exclusive of the lift cylinder 27 are provided to accurately limitthe depth of cut and to provide an accurate adjustment which may bepreset according to the depth of cut desired. For this purpose, a pairof arms 70 and 71, Figs. 1, 3, 4 and 5, are pivoted on a horizontal axisat 72 and 73, respectively, on the side frame members 33 and 34,vertically above the axis of shaft 50.

The arms 70 and 71 are guided at their upper horizontal end portionslike 70' in inverted U-shaped members 74 and 75 welded to the carriageplate 20 and to cross member 23'. Adjustable limit screws 76 and 77 arethreaded in the members 74 and 75 to engage end portions like 70' andlimit the vertical movement of the arms. Lock nuts, like nut 78, areprovided to lock the screws 76 and 77 in different adjusted positions.When the frame 23 is raised to its transporting position shown in FIG.6, arms 70 and 71 engage the top of the plate 20 and are thus raised,with their wheeled supports, like 80, with the frame. A wheeled support,like support 80, is mounted on each of the arms 70 and 71, and eachcomprises a pair of wheels 81 and 82 rotatably mounted at opposite endsof a wheel truck 83 pivotally attached at its center at 84 to a column85 integral with and depending from the respective arm.

By adjusting limit screws 76 and 77 relative to each other, the frame23, and hence the cutter 47, may be tilted slightly or not in atransverse direction relative to the level of the pavement.

From the above, it will be seen that, when the rear end of the frame 23is lowered by the hydraulic cylinder 27, the cutting disks 48 willengage the surface of the pavement. At substantially this time, thewheels 81 and 82 also engage the pavement, rocking the arms 70 and 71upward on pivots 72, 73 until arrested by the limit screws 76 and 77.The screws 76 and 77 are preferably preadjusted so that the cuttingdisks 48 will cut to a predetermined depth in any bump or short rise, asindicated at 86, FIGS. 1 and 5. Therefore, a fine and accurate controlof the lift cylinder 27 is not required.

As seen in FIG. 6, when hydraulic pressure is applied below the pistonof the cylinder 27, to extend piston rod 27', the carriage 18 will bedriven up along the mast assembly, causing the cutter frame 23 to rockupwardly in the direction of the arrow A about the axis of wheels 38 and40. Likewise, the truck 11 will be caused to similarly rock in thedirection of the arrow B about its wheels 12; but in all cases the truckframe 14 will remain parallel to the frame 23, due to the uprightsliding connection between them provided by the mast assembly 13.

Hydraulic power for enabling remote control of the steering cylinder 46,clutch control cylinder 68 and lift cylinder 27 is derived from ahydraulic pump driven by the truck motor 24. For this purpose, FIG. 8,the steering wheel at 32 controls a valve 91 connected in a fluidcircuit between the pump 90 and the opposite ends of the steeringcylinder 46, as well known. A lift cylinder control valve 92, withinreach of the operator, is connected in circuit between the pump 90 andopposite ends of the lift cylinder 27. Likewise, a clutch control valve93, also within reach of the operator, is connected in circuit betweenthe pump 90 and opposite ends of the clutch control cylinder 68.

The truck transmission 25 is controlled by a gear shift lever 94, FIG.1, whereby the machine may be selectively driven at a slow rate ofspeed, as when cutting, or a fast rate when transporting from one placeto another.

As noted heretofore, since the machine may be readily adjusted to cutanti-skid grooves in a pavement, for this purpose the cutter 47 isreplaced by a similar cutter wherein the abrasive disks are spacedfurther apart, i.e., with a spacing on the order of 0.375 inches betweenadjacent disks. In this case, see FIG. 7, a downwardly curved bracket,like bracket 96, is secured to each of the arms 70 and 71 by bolts like97. A wheeled support comprising a wheel 98 is rotatably mounted on anarm 100 pivoted at 101 to each bracket 96, and extends directly in frontof the cutter 47. An adjustment screw 102 is threaded through the arm100 and engages the bracket 96 to swing the arm 100 relative to itsbracket whereby to provide a height adjustment for the rear of theassociated arm 70 or 71 independently of the stop screws 76 and 77,which, in this case, are preferably backed off.

FIG. 7 shows the screw 102 at one extreme of its adjustment wherein theextension 70 of arm 70 rests on the top of the carriage plate 20.

As the cutter frame 23 is lowered, the wheels 81, 82 and 98 engage thepavement on opposite sides of the cutter, and by adjusting the screw102, the depth of cut of the groove-cutting disks can be accuratelyadjusted without requiring close attention by the operator.

The abrasive disks are cooled by a spray of water forced throughorifices of 103 spaced along a pipe 104 supported from the side framemembers 33 and 34 by brackets 106 and 107. An indicator rod 108 issuspended from the front end of the frame 23 to aid the operator insteering the machine along a line or previous cut or grooved section ofthe pavement.

Various modifications may be made in the invention within the scope ofthe following claims.

We claim: 1. A self-propelled pavement cutting machine comprising adrive truck having a front end, 7 a vehicle having front wheels, rearwheels and an elongated pavement cutter intermediate said front and rearwheels, said cutter extending transversely of the direction of travel,said vehicle having a rear end, an upright sliding coupling between thefront end of said drive truck and the rear end of said vehicle,

fluid pressure means operative at certain times to raise and support therear end of said vehicle with its rear wheels and cutter in elevatedposition and with the front end of said vehicle supported by said frontwheels for transportation to another location, said fluid pressure meansbeing operative at other times to lower the rear end of said vehicle forsupport by its said front and rear wheels and with said cutter incutting relation with the pavement, and

means at each end of said cutter for controlling the depth of cut whensaid cutter is in operative relation with the pavement.

2. Machine according to claim 1, said coupling being arranged onopposite sides of the longitudinal center of said truck and vehicle toprevent side sway while said vehicleis being driven by said truck.

3. Machine according to claim 1, said coupling comprising uprightU-channels facing the center line of said truck and vehicle and arrangedon opposite sides of said center line, vertically spaced rollers in eachof said channels, the front of said truck and the rear of said vehicleeach having a frame member, said channels being carried by one of saidmembers and said rollers being carried by the other of said members.

4. Machine according to claim 1, said truck having only front wheelswhich are traction wheels driven by an engine on said truck, the rearend of said truck being unsupported by the pavement and tilting up ordown substantially like the tilt movement of the rear end of saidvehicle when said fluid pressure means is operated.

5. A concrete cutting machine comprising a drive truck including a setof coaxially arranged drive wheels supporting said truck for movementover pavement,

an upright mast on said truck,

a vehicle movable over said pavement,

said vehicle comprising a frame movable about a horizontal axis,

a rotatable cutter carried by said frame, said cutter being rotatable onan axis extending transversely of said vehicle,

a carriage carried by said frame adjacent the rear of said frame,

said carriage being guided by said mast for movement along said mast,

means for moving said carriage along said mast to raise or lower saidframe and said cutter about said horizontal axis and relative to saidpavement, and

means for driving said drive wheels and said cutter.

6. Machine according to claim 5 wherein said driving means comprises afirst motor on said truck for driving said drive wheels and a secondmotor on said frame for driving said cutter.

7. Machine according to Claim 5 wherein said vehi- 20 cle comprisesfront wheels supporting said frame ad jacent the front end of said framefor movement over said pavement and for tilt movement of said vehicleabout said front wheels as said carriage moves up and down, and meansfor steering said front wheels.

8. Machine according to claim 5 comprising an arm having a pivotalconnection with said frame on a horizontal axis vertically above saidcutter axis,

a wheeled support for said vehicle on said arm on one side of saidpivotal connection,

said wheeled support having wheels engagable with said pavementintermediate said set of drive wheels and said cutter, and

adjustable means to adjustably limit the position of the outer end ofsaid arm to adjust the vertical position of said wheeled support withrespect to said cutter. 9. Machine according to claim 8 comprising meanson said frame engagable with the outer portion of one end of said armfor raising said arm and said wheeled support upon raising said frame.

10. Machine according to claim 8, said adjustable means comprising meansproviding a recess in which said outer end of said arm is verticallymovable, and an adjusting screw to limit the vertical position of saidouter end of said arm.

11. Machine according to claim 8 comprising a second wheeled support forsaid vehicle on said arm on the other side of said pivotal connection,

said second wheeled support being engagable with said pavement on theside of said cutter opposite said first-mentioned wheeled support, and

means for adjusting the vertical position of said second wheeled supportrelative to said pivotal connection.

12. Machine according to claim 11 comprising means for removablysupporting said second wheeled support on said arm.

13. A concrete cutting machine comprising a drive truck including a setof coaxially arranged drive wheels supporting said truck for movementover pavement,

first motor means for driving said drive wheels,

an upright mast on said truck,

a cutter frame,

a set of front wheels supporting said cutter frame adjacent the frontthereof for movement over said pavement,

a carriage carried by said cutter frame adjacent the rear thereof,

means supporting said carriage for movement along said mast,

a rotatable cutter carried by said frame intermediate said drive wheelsand said front wheels, said cutter being rotatable on an axis extendingtransversely of the direction of travel,

second motor means for rotating said cutter,

means for moving said carriage along said mast to raise or lower saidframe with said cutter relative to said pavement,

an arm having a pivotal connection with said frame on a horizontal axisvertically above said cutter axis,

a wheeled support for said frame on said arm between said pivotalconnection and an outer end of said arm,

said wheeled support having wheels engagable with said pavementintermediate said cutter and said drive wheels, and

adjustable stop means between said outer end of said arm and said frameto limit the upward movement of said outer end of said arm to therebylimit the downward movement of said frame and said cutter as said armpartakes of pivotal movement about said wheeled support, said wheeledsupport having wheels pivotally connected to and arranged at the frontand rear of a column fixed to said arm.

1. A self-propelled pavement cutting machine comprising a drive truckhaving a front end, a vehicle having front wheels, rear wheels and anelongated pavement cutter intermediate said front and rear wheels, saidcutter extending transversely of the direction of travel, said vehiclehaving a rear end, an upright sliding coupling between the front end ofsaid drive truck and the rear end of said vehicle, fluid pressure meansoperative at certain times to raise and support the rear end of saidvehicle with its rear wheels and cutter in elevated position and withthe front end of said vehicle supported by said front wheels fortransportation to another location, said fluid pressure means beingoperative at other times to lower the rear end of said vehicle forsupport by its said front and rear wheels and with said cutter incutting relation with the pavement, and means at each end of said cutterfor cOntrolling the depth of cut when said cutter is in operativerelation with the pavement.
 2. Machine according to claim 1, saidcoupling being arranged on opposite sides of the longitudinal center ofsaid truck and vehicle to prevent side sway while said vehicle is beingdriven by said truck.
 3. Machine according to claim 1, said couplingcomprising upright U-channels facing the center line of said truck andvehicle and arranged on opposite sides of said center line, verticallyspaced rollers in each of said channels, the front of said truck and therear of said vehicle each having a frame member, said channels beingcarried by one of said members and said rollers being carried by theother of said members.
 4. Machine according to claim 1, said truckhaving only front wheels which are traction wheels driven by an engineon said truck, the rear end of said truck being unsupported by thepavement and tilting up or down substantially like the tilt movement ofthe rear end of said vehicle when said fluid pressure means is operated.5. A concrete cutting machine comprising a drive truck including a setof coaxially arranged drive wheels supporting said truck for movementover pavement, an upright mast on said truck, a vehicle movable oversaid pavement, said vehicle comprising a frame movable about ahorizontal axis, a rotatable cutter carried by said frame, said cutterbeing rotatable on an axis extending transversely of said vehicle, acarriage carried by said frame adjacent the rear of said frame, saidcarriage being guided by said mast for movement along said mast, meansfor moving said carriage along said mast to raise or lower said frameand said cutter about said horizontal axis and relative to saidpavement, and means for driving said drive wheels and said cutter. 6.Machine according to claim 5 wherein said driving means comprises afirst motor on said truck for driving said drive wheels and a secondmotor on said frame for driving said cutter.
 7. Machine according toClaim 5 wherein said vehicle comprises front wheels supporting saidframe adjacent the front end of said frame for movement over saidpavement and for tilt movement of said vehicle about said front wheelsas said carriage moves up and down, and means for steering said frontwheels.
 8. Machine according to claim 5 comprising an arm having apivotal connection with said frame on a horizontal axis vertically abovesaid cutter axis, a wheeled support for said vehicle on said arm on oneside of said pivotal connection, said wheeled support having wheelsengagable with said pavement intermediate said set of drive wheels andsaid cutter, and adjustable means to adjustably limit the position ofthe outer end of said arm to adjust the vertical position of saidwheeled support with respect to said cutter.
 9. Machine according toclaim 8 comprising means on said frame engagable with the outer portionof one end of said arm for raising said arm and said wheeled supportupon raising said frame.
 10. Machine according to claim 8, saidadjustable means comprising means providing a recess in which said outerend of said arm is vertically movable, and an adjusting screw to limitthe vertical position of said outer end of said arm.
 11. Machineaccording to claim 8 comprising a second wheeled support for saidvehicle on said arm on the other side of said pivotal connection, saidsecond wheeled support being engagable with said pavement on the side ofsaid cutter opposite said first-mentioned wheeled support, and means foradjusting the vertical position of said second wheeled support relativeto said pivotal connection.
 12. Machine according to claim 11 comprisingmeans for removably supporting said second wheeled support on said arm.13. A concrete cutting machine comprising a drive truck including a setof coaxially arranged drive wheels supporting said truck for movementover pavement, first motor means for driving said drive wheels, anupright mast on said truck, a cutter frame, a set of front wheelssupporting said cutter frame adjacent the front thereof for movementover said pavement, a carriage carried by said cutter frame adjacent therear thereof, means supporting said carriage for movement along saidmast, a rotatable cutter carried by said frame intermediate said drivewheels and said front wheels, said cutter being rotatable on an axisextending transversely of the direction of travel, second motor meansfor rotating said cutter, means for moving said carriage along said mastto raise or lower said frame with said cutter relative to said pavement,an arm having a pivotal connection with said frame on a horizontal axisvertically above said cutter axis, a wheeled support for said frame onsaid arm between said pivotal connection and an outer end of said arm,said wheeled support having wheels engagable with said pavementintermediate said cutter and said drive wheels, and adjustable stopmeans between said outer end of said arm and said frame to limit theupward movement of said outer end of said arm to thereby limit thedownward movement of said frame and said cutter as said arm partakes ofpivotal movement about said wheeled support, said wheeled support havingwheels pivotally connected to and arranged at the front and rear of acolumn fixed to said arm.